1. Field of the Invention
The present invention relates to a self-diagnosing apparatus and a method for a video recording and reproducing apparatus, and in particular to an improved self-diagnosing apparatus and a method for a video recording and reproducing apparatus which are capable of detecting the errors of parts of the apparatus, and classifying the errors for thus more effectively correcting the errors.
2. Description of the Conventional Art
FIG. 1 illustrates a conventional self-diagnosing content display apparatus for a video cassette tape recorder (VCR).
As shown therein, the conventional self-diagnosing content display apparatus for a VCR includes a microcomputer 1 for controlling the entire operation of an apparatus and controlling a self-diagnosing content display operation, a dew formation detection unit 2 for detecting a dew formation on a head drum and inputting a data corresponding to the dew formation detection into the microcomputer 1, a servo unit 3 for generating hardware signals of 30 Hz and 25 Hz in accordance with an NTSC and PAL method and inputting the signals into the microcomputer 1, a deck unit 5 for converting the operation mode in accordance with a control of the microcomputer 1, a motor driving unit 4 for controlling the operation of the deck unit 5, a reel pulse signal detection unit 6 for detecting a reel pulse signal produced during a video tape running operation by the deck unit 5 and inputting the signal into the microcomputer 1, a synchronous signal detection unit 7 for detecting a synchronous signal from the inputted video signal, and a display unit 8 for generating a character signal corresponding to the error and mixing the signal with a video signal in accordance with the control of the microcomputer 1.
The deck unit 5 includes a mode conversion motor 5-1 driven in accordance with a control of the motor driving unit 4 for converting the operation mode, and a mode switch unit 5-2 for detecting the converted operation mode and inputting the detected mode into the microcomputer 1.
The operation of a conventional self-diagnosing content display apparatus for a VCR will now be explained with reference to the accompanying drawings.
First, the dew formation detection unit 2 detects a dew formation on the head drum, and inputs the detected result into the microcomputer 1, and the servo unit 3 generates hardware signals of 30 Hz and 25 Hz in accordance with an NTSC and PAL method when reproducing the recorded tape by using the servo unit 3 and inputs the signals into the microcomputer 1.
Thereafter, the microcomputer 1 controls the mode conversion motor 5-1 of the deck unit 5 through the motor driving unit 4 for thus setting the operation mode of the deck unit 5. In addition, the mode switch unit 5-2 detects the set operation mode and inputs the detected mode into the microcomputer 1. The video tape is run by the deck unit 5, and the reel pulse signal detection unit 6 detects the reel pulse signals which are produced during the tape running operation and inputs the signals into the microcomputer 1.
Therefore, the microcomputer 1 judges whether there is an error in the apparatus by using the output signals from the dew formation unit 2, the servo unit 3, the mode switch unit 5-1, and the reel pulse signal detection unit 6. If there is an error, a character signal corresponding to the error is generated, and the display unit 8 judges whether a video signal is inputted in accordance with an output signal from the synchronous signal detection unit 7. If there exists a video signal, the character signal is mixed with the video signal. If there is not a video signal, the character signal is outputted in accordance with an internal synchronous signal for thus informing a user of the fact that the error occurred.
In addition, FIGS. 2A and 2B illustrate a conventional self-diagnosing content display method for a VCR.
As shown therein, the conventional self-diagnosing content display method for a VCR includes a first step for detecting whether dew is formed on the head drum when driving a video tape, a second step for displaying a character signal and error content that a dew is formed on the head drum as a result of the dew formation detection and stopping the display operation after a predetermined time, a third step for judging whether a hardware signal is inputted during a normal speed reproducing operation, a fast forward direction reproducing operation or a fast reverse direction reproducing operation when dew is not formed on the head drum as a result of the first step, a fourth step for displaying a character signal and error content when the hardware signal is not inputted and stopping the display operation after a predetermined time, a fifth step for judging whether a reel pulse signal is inputted after judging whether the video tape is driven in the fast winding mode, the rewinding mode, or the recording mode when the hardware signal is inputted during the normal speed reproducing operation, the fast forward direction reproducing operation or the fast reverse direction reproducing operation as a result of the judgement of the third step, a sixth step for displaying a character signal and error content by judging the operation of the apparatus as the motor is not driven when the reel pulse signal is not inputted as a result of the judgement and stopping the display operation after a predetermined time, a seventh step for judging whether a desired operation mode is set within the set time in accordance with the output signal from the mode switch unit during the mode conversion operation by judging whether the operation is currently performed in the mode conversion operation when the video tape operation is not in the fast winding mode, the rewinding mode, and the recording mode as a result of the fifth step, and an eighth step for displaying a character signal and error content when the desired operation mode is not set as a result of the judgement and stopping the display operation after a predetermined time.
In the conventional self-diagnosing content display method for a VCR, it is judged whether dew is formed on the head drum in accordance with the output signal from the dew formation detection unit. If dew is formed thereon, a character signal and error content such as "Dew is formed on the head drum" is displayed, and then the display operation is stopped after a predetermined time.
In the normal speed reproducing mode (PB), the fast forward direction reproducing (CUE) mode, or the fast reverse direction reproducing (REV) mode, it is judged whether a hardware signal is inputted thereinto from the servo unit 3, and then a character signal and error content such as "The head drum is not rotated" is displayed, and the display operation is stopped after a predetermined time.
In addition, if a hardware signal is inputted in the normal speed reproducing mode, the fast forward direction reproducing mode, or the fast reverse direction reproducing mode, or if the operation mode is performed in the fast forward winding mode (FF), the rewinding mode (REW), or the recording mode (REC), it is judged whether a reel pulse signal is inputted thereinto from the reel pulse signal detection unit 6. If the reel pulse signal is not inputted as a result of the judgement, it is judged that the capstan motor is not driven. Thereafter, a character signal and error content such as "The capstan motor is not rotated" is displayed, and the display operation is stopped after a predetermined time.
In addition, in the conversion mode, it is judged whether a desired operation mode is set within a set time in accordance with the output signal from the mode switch unit 5-2. If the operation mode is not set, it is judged that the mode conversion motor 5-1 is not driven. Thereafter, a character signal and error content such as "The operation mode is not set" is displayed, and the display operation is stopped after a predetermined time.
As described above, since the conventional self-diagnosing content display apparatus and a method for a VCR does not include an apparatus which is capable of self-diagnosing the operation of the apparatus, it is impossible to accurately diagnose the apparatus. In addition, if an error occurs in the apparatus, a user may erroneously operate the apparatus for thus causing a critical damage to the apparatus. In addition, due to the damages, the life span of the apparatus may be shortened.